/* * NSV demuxer * Copyright (c) 2004 The FFmpeg Project * * first version by Francois Revol <revol@free.fr> * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/attributes.h" #include "libavutil/mathematics.h" #include "avformat.h" #include "internal.h" #include "libavutil/dict.h" #include "libavutil/intreadwrite.h" /* max bytes to crawl for trying to resync * stupid streaming servers don't start at chunk boundaries... */ #define NSV_MAX_RESYNC (500*1024) #define NSV_MAX_RESYNC_TRIES 300 /* * References: * (1) http://www.multimedia.cx/nsv-format.txt * seems someone came to the same conclusions as me, and updated it: * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt * http://www.stud.ktu.lt/~vitslav/nsv/ * official docs * (3) http://ultravox.aol.com/NSVFormat.rtf * Sample files: * (S1) http://www.nullsoft.com/nsv/samples/ * http://www.nullsoft.com/nsv/samples/faster.nsv * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4 */ /* * notes on the header (Francois Revol): * * It is followed by strings, then a table, but nothing tells * where the table begins according to (1). After checking faster.nsv, * I believe NVSf[16-19] gives the size of the strings data * (that is the offset of the data table after the header). * After checking all samples from (S1) all confirms this. * * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC, * I noticed there was about 1 NVSs chunk/s, so I ran * strings faster.nsv | grep NSVs | wc -l * which gave me 180. That leads me to think that NSVf[12-15] might be the * file length in milliseconds. * Let's try that: * for f in *.nsv; do HTIME="$(od -t x4 "$f" | head -1 | sed 's/.* //')"; echo "'$f' $((0x$HTIME))s = $((0x$HTIME/1000/60)):$((0x$HTIME/1000%60))"; done * except for nstrailer (which doesn't have an NSVf header), it repports correct time. * * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks, * so the header seems to not be mandatory. (for streaming). * * index slice duration check (excepts nsvtrailer.nsv): * for f in [^n]*.nsv; do DUR="$(ffmpeg -i "$f" 2>/dev/null | grep 'NSVf duration' | cut -d ' ' -f 4)"; IC="$(ffmpeg -i "$f" 2>/dev/null | grep 'INDEX ENTRIES' | cut -d ' ' -f 2)"; echo "duration $DUR, slite time $(($DUR/$IC))"; done */ /* * TODO: * - handle timestamps !!! * - use index * - mime-type in probe() * - seek */ #if 0 struct NSVf_header { uint32_t chunk_tag; /* 'NSVf' */ uint32_t chunk_size; uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */ uint32_t file_length; //unknown1; /* what about MSB of file_size ? */ uint32_t info_strings_size; /* size of the info strings */ //unknown2; uint32_t table_entries; uint32_t table_entries_used; /* the left ones should be -1 */ }; struct NSVs_header { uint32_t chunk_tag; /* 'NSVs' */ uint32_t v4cc; /* or 'NONE' */ uint32_t a4cc; /* or 'NONE' */ uint16_t vwidth; /* av_assert0(vwidth%16==0) */ uint16_t vheight; /* av_assert0(vheight%16==0) */ uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */ uint16_t unknown; }; struct nsv_avchunk_header { uint8_t vchunk_size_lsb; uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */ uint16_t achunk_size; }; struct nsv_pcm_header { uint8_t bits_per_sample; uint8_t channel_count; uint16_t sample_rate; }; #endif /* variation from avi.h */ /*typedef struct CodecTag { int id; unsigned int tag; } CodecTag;*/ /* tags */ #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */ #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */ #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */ #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */ #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */ #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */ #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */ #define TB_NSVF MKBETAG('N', 'S', 'V', 'f') #define TB_NSVS MKBETAG('N', 'S', 'V', 's') /* hardcoded stream indexes */ #define NSV_ST_VIDEO 0 #define NSV_ST_AUDIO 1 #define NSV_ST_SUBT 2 enum NSVStatus { NSV_UNSYNC, NSV_FOUND_NSVF, NSV_HAS_READ_NSVF, NSV_FOUND_NSVS, NSV_HAS_READ_NSVS, NSV_FOUND_BEEF, NSV_GOT_VIDEO, NSV_GOT_AUDIO, }; typedef struct NSVStream { int frame_offset; /* current frame (video) or byte (audio) counter (used to compute the pts) */ int scale; int rate; int sample_size; /* audio only data */ int start; int new_frame_offset; /* temporary storage (used during seek) */ int cum_len; /* temporary storage (used during seek) */ } NSVStream; typedef struct { int base_offset; int NSVf_end; uint32_t *nsvs_file_offset; int index_entries; enum NSVStatus state; AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */ /* cached */ int64_t duration; uint32_t vtag, atag; uint16_t vwidth, vheight; int16_t avsync; AVRational framerate; uint32_t *nsvs_timestamps; //DVDemuxContext* dv_demux; } NSVContext; static const AVCodecTag nsv_codec_video_tags[] = { { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') }, { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') }, { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') }, { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') }, { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') }, { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') }, { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') }, { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') }, { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') }, { AV_CODEC_ID_VP8, MKTAG('V', 'P', '8', '0') }, /* { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') }, { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') }, */ { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */ { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') }, { AV_CODEC_ID_NONE, 0 }, }; static const AVCodecTag nsv_codec_audio_tags[] = { { AV_CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') }, { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') }, { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') }, { AV_CODEC_ID_AAC, MKTAG('V', 'L', 'B', ' ') }, { AV_CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') }, { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') }, { AV_CODEC_ID_NONE, 0 }, }; //static int nsv_load_index(AVFormatContext *s); static int nsv_read_chunk(AVFormatContext *s, int fill_header); #define print_tag(str, tag, size) \ av_dlog(NULL, "%s: tag=%c%c%c%c\n", \ str, tag & 0xff, \ (tag >> 8) & 0xff, \ (tag >> 16) & 0xff, \ (tag >> 24) & 0xff); /* try to find something we recognize, and set the state accordingly */ static int nsv_resync(AVFormatContext *s) { NSVContext *nsv = s->priv_data; AVIOContext *pb = s->pb; uint32_t v = 0; int i; av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state); //nsv->state = NSV_UNSYNC; for (i = 0; i < NSV_MAX_RESYNC; i++) { if (avio_feof(pb)) { av_dlog(s, "NSV EOF\n"); nsv->state = NSV_UNSYNC; return -1; } v <<= 8; v |= avio_r8(pb); if (i < 8) { av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF); } if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */ av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1); nsv->state = NSV_FOUND_BEEF; return 0; } /* we read as big-endian, thus the MK*BE* */ if (v == TB_NSVF) { /* NSVf */ av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1); nsv->state = NSV_FOUND_NSVF; return 0; } if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */ av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1); nsv->state = NSV_FOUND_NSVS; return 0; } } av_dlog(s, "NSV sync lost\n"); return -1; } static int nsv_parse_NSVf_header(AVFormatContext *s) { NSVContext *nsv = s->priv_data; AVIOContext *pb = s->pb; unsigned int av_unused file_size; unsigned int size; int64_t duration; int strings_size; int table_entries; int table_entries_used; av_dlog(s, "%s()\n", __FUNCTION__); nsv->state = NSV_UNSYNC; /* in case we fail */ size = avio_rl32(pb); if (size < 28) return -1; nsv->NSVf_end = size; //s->file_size = (uint32_t)avio_rl32(pb); file_size = (uint32_t)avio_rl32(pb); av_dlog(s, "NSV NSVf chunk_size %u\n", size); av_dlog(s, "NSV NSVf file_size %u\n", file_size); nsv->duration = duration = avio_rl32(pb); /* in ms */ av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration); // XXX: store it in AVStreams strings_size = avio_rl32(pb); table_entries = avio_rl32(pb); table_entries_used = avio_rl32(pb); av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n", strings_size, table_entries, table_entries_used); if (avio_feof(pb)) return -1; av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb)); if (strings_size > 0) { char *strings; /* last byte will be '\0' to play safe with str*() */ char *p, *endp; char *token, *value; char quote; p = strings = av_mallocz((size_t)strings_size + 1); if (!p) return AVERROR(ENOMEM); endp = strings + strings_size; avio_read(pb, strings, strings_size); while (p < endp) { while (*p == ' ') p++; /* strip out spaces */ if (p >= endp-2) break; token = p; p = strchr(p, '='); if (!p || p >= endp-2) break; *p++ = '\0'; quote = *p++; value = p; p = strchr(p, quote); if (!p || p >= endp) break; *p++ = '\0'; av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value); av_dict_set(&s->metadata, token, value, 0); } av_free(strings); } if (avio_feof(pb)) return -1; av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb)); if (table_entries_used > 0) { int i; nsv->index_entries = table_entries_used; if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t)) return -1; nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t)); if (!nsv->nsvs_file_offset) return AVERROR(ENOMEM); for(i=0;i<table_entries_used;i++) nsv->nsvs_file_offset[i] = avio_rl32(pb) + size; if(table_entries > table_entries_used && avio_rl32(pb) == MKTAG('T','O','C','2')) { nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t)); if (!nsv->nsvs_timestamps) return AVERROR(ENOMEM); for(i=0;i<table_entries_used;i++) { nsv->nsvs_timestamps[i] = avio_rl32(pb); } } } av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb)); avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */ if (avio_feof(pb)) return -1; nsv->state = NSV_HAS_READ_NSVF; return 0; } static int nsv_parse_NSVs_header(AVFormatContext *s) { NSVContext *nsv = s->priv_data; AVIOContext *pb = s->pb; uint32_t vtag, atag; uint16_t vwidth, vheight; AVRational framerate; int i; AVStream *st; NSVStream *nst; av_dlog(s, "%s()\n", __FUNCTION__); vtag = avio_rl32(pb); atag = avio_rl32(pb); vwidth = avio_rl16(pb); vheight = avio_rl16(pb); i = avio_r8(pb); av_dlog(s, "NSV NSVs framerate code %2x\n", i); if(i&0x80) { /* odd way of giving native framerates from docs */ int t=(i & 0x7F)>>2; if(t<16) framerate = (AVRational){1, t+1}; else framerate = (AVRational){t-15, 1}; if(i&1){ framerate.num *= 1000; framerate.den *= 1001; } if((i&3)==3) framerate.num *= 24; else if((i&3)==2) framerate.num *= 25; else framerate.num *= 30; } else framerate= (AVRational){i, 1}; nsv->avsync = avio_rl16(pb); nsv->framerate = framerate; print_tag("NSV NSVs vtag", vtag, 0); print_tag("NSV NSVs atag", atag, 0); av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight); /* XXX change to ap != NULL ? */ if (s->nb_streams == 0) { /* streams not yet published, let's do that */ nsv->vtag = vtag; nsv->atag = atag; nsv->vwidth = vwidth; nsv->vheight = vwidth; if (vtag != T_NONE) { int i; st = avformat_new_stream(s, NULL); if (!st) goto fail; st->id = NSV_ST_VIDEO; nst = av_mallocz(sizeof(NSVStream)); if (!nst) goto fail; st->priv_data = nst; st->codec->codec_type = AVMEDIA_TYPE_VIDEO; st->codec->codec_tag = vtag; st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag); st->codec->width = vwidth; st->codec->height = vheight; st->codec->bits_per_coded_sample = 24; /* depth XXX */ avpriv_set_pts_info(st, 64, framerate.den, framerate.num); st->start_time = 0; st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den); for(i=0;i<nsv->index_entries;i++) { if(nsv->nsvs_timestamps) { av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i], 0, 0, AVINDEX_KEYFRAME); } else { int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den); av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME); } } } if (atag != T_NONE) { st = avformat_new_stream(s, NULL); if (!st) goto fail; st->id = NSV_ST_AUDIO; nst = av_mallocz(sizeof(NSVStream)); if (!nst) goto fail; st->priv_data = nst; st->codec->codec_type = AVMEDIA_TYPE_AUDIO; st->codec->codec_tag = atag; st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag); st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */ /* set timebase to common denominator of ms and framerate */ avpriv_set_pts_info(st, 64, 1, framerate.num*1000); st->start_time = 0; st->duration = (int64_t)nsv->duration * framerate.num; } } else { if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) { av_dlog(s, "NSV NSVs header values differ from the first one!!!\n"); //return -1; } } nsv->state = NSV_HAS_READ_NSVS; return 0; fail: /* XXX */ nsv->state = NSV_UNSYNC; return -1; } static int nsv_read_header(AVFormatContext *s) { NSVContext *nsv = s->priv_data; int i, err; av_dlog(s, "%s()\n", __FUNCTION__); av_dlog(s, "filename '%s'\n", s->filename); nsv->state = NSV_UNSYNC; nsv->ahead[0].data = nsv->ahead[1].data = NULL; for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) { if (nsv_resync(s) < 0) return -1; if (nsv->state == NSV_FOUND_NSVF) { err = nsv_parse_NSVf_header(s); if (err < 0) return err; } /* we need the first NSVs also... */ if (nsv->state == NSV_FOUND_NSVS) { err = nsv_parse_NSVs_header(s); if (err < 0) return err; break; /* we just want the first one */ } } if (s->nb_streams < 1) /* no luck so far */ return -1; /* now read the first chunk, so we can attempt to decode more info */ err = nsv_read_chunk(s, 1); av_dlog(s, "parsed header\n"); return err; } static int nsv_read_chunk(AVFormatContext *s, int fill_header) { NSVContext *nsv = s->priv_data; AVIOContext *pb = s->pb; AVStream *st[2] = {NULL, NULL}; NSVStream *nst; AVPacket *pkt; int i, err = 0; uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */ uint32_t vsize; uint16_t asize; uint16_t auxsize; av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header); if (nsv->ahead[0].data || nsv->ahead[1].data) return 0; //-1; /* hey! eat what you've in your plate first! */ null_chunk_retry: if (avio_feof(pb)) return -1; for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++) err = nsv_resync(s); if (err < 0) return err; if (nsv->state == NSV_FOUND_NSVS) err = nsv_parse_NSVs_header(s); if (err < 0) return err; if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF) return -1; auxcount = avio_r8(pb); vsize = avio_rl16(pb); asize = avio_rl16(pb); vsize = (vsize << 4) | (auxcount >> 4); auxcount &= 0x0f; av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize); /* skip aux stuff */ for (i = 0; i < auxcount; i++) { uint32_t av_unused auxtag; auxsize = avio_rl16(pb); auxtag = avio_rl32(pb); av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n", (auxtag & 0x0ff), ((auxtag >> 8) & 0x0ff), ((auxtag >> 16) & 0x0ff), ((auxtag >> 24) & 0x0ff), auxsize); avio_skip(pb, auxsize); vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */ } if (avio_feof(pb)) return -1; if (!vsize && !asize) { nsv->state = NSV_UNSYNC; goto null_chunk_retry; } /* map back streams to v,a */ if (s->nb_streams > 0) st[s->streams[0]->id] = s->streams[0]; if (s->nb_streams > 1) st[s->streams[1]->id] = s->streams[1]; if (vsize && st[NSV_ST_VIDEO]) { nst = st[NSV_ST_VIDEO]->priv_data; pkt = &nsv->ahead[NSV_ST_VIDEO]; av_get_packet(pb, pkt, vsize); pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO; pkt->dts = nst->frame_offset; pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */ for (i = 0; i < FFMIN(8, vsize); i++) av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]); } if(st[NSV_ST_VIDEO]) ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++; if (asize && st[NSV_ST_AUDIO]) { nst = st[NSV_ST_AUDIO]->priv_data; pkt = &nsv->ahead[NSV_ST_AUDIO]; /* read raw audio specific header on the first audio chunk... */ /* on ALL audio chunks ?? seems so! */ if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) { uint8_t bps; uint8_t channels; uint16_t samplerate; bps = avio_r8(pb); channels = avio_r8(pb); samplerate = avio_rl16(pb); asize-=4; av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate); if (fill_header) { st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */ if (bps != 16) { av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps); } if(channels) bps /= channels; // ??? else av_log(s, AV_LOG_WARNING, "Channels is 0\n"); if (bps == 8) st[NSV_ST_AUDIO]->codec->codec_id = AV_CODEC_ID_PCM_U8; samplerate /= 4;/* UGH ??? XXX */ channels = 1; st[NSV_ST_AUDIO]->codec->channels = channels; st[NSV_ST_AUDIO]->codec->sample_rate = samplerate; av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate); } } av_get_packet(pb, pkt, asize); pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO; pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */ if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) { /* on a nsvs frame we have new information on a/v sync */ pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1); pkt->dts *= (int64_t)1000 * nsv->framerate.den; pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num; av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts); } nst->frame_offset++; } nsv->state = NSV_UNSYNC; return 0; } static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt) { NSVContext *nsv = s->priv_data; int i, err = 0; av_dlog(s, "%s()\n", __FUNCTION__); /* in case we don't already have something to eat ... */ if (!nsv->ahead[0].data && !nsv->ahead[1].data) err = nsv_read_chunk(s, 0); if (err < 0) return err; /* now pick one of the plates */ for (i = 0; i < 2; i++) { if (nsv->ahead[i].data) { av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i); /* avoid the cost of new_packet + memcpy(->data) */ memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket)); nsv->ahead[i].data = NULL; /* we ate that one */ return pkt->size; } } /* this restaurant is not approvisionned :^] */ return -1; } static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) { NSVContext *nsv = s->priv_data; AVStream *st = s->streams[stream_index]; NSVStream *nst = st->priv_data; int index; index = av_index_search_timestamp(st, timestamp, flags); if(index < 0) return -1; if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0) return -1; nst->frame_offset = st->index_entries[index].timestamp; nsv->state = NSV_UNSYNC; return 0; } static int nsv_read_close(AVFormatContext *s) { NSVContext *nsv = s->priv_data; av_freep(&nsv->nsvs_file_offset); av_freep(&nsv->nsvs_timestamps); if (nsv->ahead[0].data) av_free_packet(&nsv->ahead[0]); if (nsv->ahead[1].data) av_free_packet(&nsv->ahead[1]); return 0; } static int nsv_probe(AVProbeData *p) { int i, score = 0; av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size); /* check file header */ /* streamed files might not have any header */ if (p->buf[0] == 'N' && p->buf[1] == 'S' && p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's')) return AVPROBE_SCORE_MAX; /* XXX: do streamed files always start at chunk boundary ?? */ /* or do we need to search NSVs in the byte stream ? */ /* seems the servers don't bother starting clean chunks... */ /* sometimes even the first header is at 9KB or something :^) */ for (i = 1; i < p->buf_size - 3; i++) { if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) { /* Get the chunk size and check if at the end we are getting 0xBEEF */ int vsize = AV_RL24(p->buf+i+19) >> 4; int asize = AV_RL16(p->buf+i+22); int offset = i + 23 + asize + vsize + 1; if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF) return 4*AVPROBE_SCORE_MAX/5; score = AVPROBE_SCORE_MAX/5; } } /* so we'll have more luck on extension... */ if (av_match_ext(p->filename, "nsv")) return AVPROBE_SCORE_EXTENSION; /* FIXME: add mime-type check */ return score; } AVInputFormat ff_nsv_demuxer = { .name = "nsv", .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"), .priv_data_size = sizeof(NSVContext), .read_probe = nsv_probe, .read_header = nsv_read_header, .read_packet = nsv_read_packet, .read_close = nsv_read_close, .read_seek = nsv_read_seek, };